Road heating device

ABSTRACT

A road heating device disposable on a road to increase a surface temperature thereof, includes a sensor configured to convert at least one of an environmental impact and a physical impact on the road heating device to electric power, an energy storage configured to store the electric power from the sensor, a heating unit configured to generate heat using the electric power stored in the energy storage, and a switch configured to selectively power the heating unit with the electric power stored in the energy storage when the surface temperature is equal to or lower than a first temperature.

CROSS REFERENCE TO PRIOR APPLICATIONS

This application claims priority and the benefit thereof under 35 U.S.C. §119(e) from a U.S. Provisional Application No. 61/089,202, filed on Aug. 15, 2008, which is hereby incorporated by reference for all purposes as if fully set forth herein.

BACKGROUND OF THE DISCLOSURE

1. Field of the Disclosure

This disclosure is directed to improving hazardous driving conditions due to low temperatures, and particularly to a road heating devices disposed on a road surface to increase a surface temperature thereof.

2. Related Art

In Winter, driving conditions deteriorate significantly due to low surface temperatures of roads, which turn snow and rain to ice quickly. The use of snow plows is costly. The use of chemicals negatively impacts the environment and also is costly. Accordingly, there is a need for preventing such hazardous driving conditions in a more economic and environmentally positive way.

SUMMARY OF THE DISCLOSURE

In one aspect of the disclosure, a road heating device disposable on a road to increase a surface temperature thereof, includes a sensor configured to convert at least one of an environmental impact and a physical impact on the road heating device to electric power, an energy storage configured to store the electric power from the sensor, a heating unit configured to generate heat using the electric power stored in the energy storage, and a switch configured to selectively power the heating unit with the electric power stored in the energy storage when the surface temperature is equal to or lower than a first temperature.

The road heating device may be micro-sized or nano-sized. The environmental impact may include heat conducted from the road to the road heating device, and the sensor may include a thermocouple sensor. The physical impact may include at least one of a pressure, a force and a strain to the road heating device, and the sensor may include a piezoelectric sensor.

The energy storage may include at least one of a battery and capacitor. The heating unit may include a resistive heating element. The first temperature may include a freezing point of water. The switch may stop power from being supplied to the heating unit when the surface temperature is equal to or higher than a melting point of ice. The road heating device may be disposed on asphalt pavement, embedded in a surface coating on asphalt, or embedded in a pavement structure.

In another aspect of the disclosure, a method for increasing a surface temperature of a road includes converting at least one of an environmental impact and a physical impact to the road to electric power, storing the electric power, and converting the stored electric power to heat when the surface temperature of the road is equal to or lower than a first temperature.

The environmental impact may include heat conducted from the road, and the physical impact may include at least one of a pressure, a force and a strain to the road. The first temperature may include a freezing point of water. The method may further include stopping converting the stored electric power to heat when the surface temperature is equal to or greater than a melting point of ice.

In another aspect of the disclosure, a device for increasing a surface temperature of a road includes a plurality of road heating devices disposed on the road. Each of the road heating devices includes a first converting unit configured to convert at least one of an environmental impact and a physical impact to electric power, an energy storage unit configured to store the electric power from the first converting unit, a second converting unit configured to convert the electric power stored in the energy storage unit to heat, and a switching unit configured to power the second converting unit when the surface temperature is equal to or lower than a first temperature.

Each road heating device may be micro-sized or nano-sized. The environmental impact may include heat conducted from the road to the road heating device, and the physical impact may include at least one of a pressure, a force and a strain to the road heating device. The first temperature may include a freezing point of water. The switching unit may stop power from being supplied to the second converting unit when the surface temperature is equal to or higher than a melting point of ice.

Additional features, advantages, and embodiments of the disclosure may be set forth or apparent from consideration of the following detailed description, drawings, and claims. Moreover, it is to be understood that both the foregoing summary of the disclosure and the following detailed description are exemplary and intended to provide further explanation without limiting the scope of the disclosure as claimed.

BRIEF DESCRIPTION OF THE DRAWINGS

The accompanying drawings, which are included to provide a further understanding of the disclosure, are incorporated in and constitute a part of this specification, illustrate embodiments of the disclosure and together with the detailed description serve to explain the principles of the disclosure. No attempt is made to show structural details of the disclosure in more detail than may be necessary for a fundamental understanding of the disclosure and the various ways in which it may be practiced. In the drawings:

FIGS. 1A and 1B illustrate a deterioration of driving conditions as a temperature drops below a freezing point of rain or snow;

FIG. 2, shows an example of a road heating device constructed according to the principles of the disclosure;

FIG. 3 shows an enlarged view of asphalt pavement treated with a bulk of the road heating devices; and

FIG. 4 shows a flowchart of a process for increasing a surface temperature of a road according to the principles of the disclosure.

DETAILED DESCRIPTION OF THE DISCLOSURE

The embodiments of the disclosure and the various features and advantageous details thereof are explained more fully with reference to the non-limiting embodiments and examples that are described and/or illustrated in the accompanying drawings and detailed in the following description. It should be noted that the features illustrated in the drawings are not necessarily drawn to scale, and features of one embodiment may be employed with other embodiments as the skilled artisan would recognize, even if not explicitly stated herein. Descriptions of well-known components and processing techniques may be omitted so as to not unnecessarily obscure the embodiments of the disclosure. The examples used herein are intended merely to facilitate an understanding of ways in which the disclosure may be practiced and to further enable those of skill in the art to practice the embodiments of the disclosure. Accordingly, the examples and embodiments herein should not be construed as limiting the scope of the disclosure, which is defined solely by the appended claims and applicable law. Moreover, it is noted that like reference numerals represent similar parts throughout the several views of the drawings.

FIGS. 1A and 1B illustrate a deterioration of driving conditions as a surface temperature of a road 100 drops below a freezing point (FP) of rain or snow. Referring to FIG. 1A, when the surface temperature of the road 100 is higher than the freezing point, the rain or even snow accumulated on the road 100 may not turn to ice and, thus, the road 100 may not be too hazardous to drive on as long as the drivers follow the safe-driving procedures, such as, e.g., driving at a reduced speed, maintaining sufficient distances from proceeding vehicles, and the like. However, as shown in FIG. 1B, when the surface temperature drops below the freezing point, the rain or snow accumulated on the road 100 may freeze and the road 100 may be covered with ice 110. This may deteriorate the driving conditions of the road 100, resulting in accidents and casualties in some cases.

According to the principles of the disclosure, the road 100 may be treated with a road heating device 200 (shown in FIGS. 2 and 3) to increase the surface temperature of the road 100. A single road heating device 200 may not generate sufficient heat to increase the surface temperature of the surrounding surface of the road 100. Thus, as shown in FIG. 3, the road 100 may be treated with a large quantity of the road heating devices 200 to accumulate the heat generated by each of the road heating device 200. The bulk of the road heating devices 200 may be disposed on asphalt pavement, embedded in a surface coating on asphalt, embedded in a pavement structure and/or the like.

The road heating device 200 may be configured such that the road heating devices 200 in the bulk form may generate heat when the surface temperature of the road 100 drops, or is about to drop below a certain temperature, such as, e.g., the freezing point of rain or snow. Furthermore, the road heating device 200 may be configured to stop generating heat when the surface temperature rises above a certain temperature, such as, e.g., a melting point of ice, to reduce power consumption.

The road heating device 200 may be self-powered, and therefore no external power may be required to generate heat. To power itself, the road heating device 200 may convert environmental and/or physical impacts to electric power. The environmental impact may include heat conducted from the surrounding road surface to the road heating device 200 and/or the like. The physical impact may include a pressure, force, strain and/or the like to the road heating device by, for example, vehicles passing over. Other types of impacts that are convertible to electric power are also contemplated.

The road heating device 200 may be micro-sized (i.e., about 100 micrometer or smaller) or nano-sized (i.e., about 100 nanometers or smaller). The micro-sized road heating device 200 may be manufactured using the micro-technology, which started in the 1960s by arranging large numbers of microscopic transistors on a single chip. The nano-sized road heating device 200 may be manufactured using the nanotechnology, which is based on the study of the control of matter on an atomic and molecular scale. The essential components of nanocircuits, such as, e.g., transistors, logic gates, diodes and/or the like, have been already developed using, for example, organic molecules, carbon nanotubes, nanowire semiconductors and/or the like. By scaling the road heating device 200 to the nano or micro level, the road 100 treated with a bulk of the road heating devices 200 may exhibit no adverse effects on driving conditions. Also, due to its microscopic size, the road heating device 200 may not negatively alter pavement conditions (e.g., strength, durability, color and/or the like).

FIG. 2 shows an exemplary configuration of the road heating device 200 constructed according to the principles of the disclosure. The road heating device 200 may include an energy storage 210, a switch 220, one or more sensors 230, one or more heating devices 240, and/or the like.

The sensors 230 may convert the environmental, physical impact and/or other type of impact to electric power. In an embodiment, the sensors 230 may include a thermocouple sensor to produce electrical power from the heat conducted from the surrounding surface of the road 100. The thermocouple sensor may be particularly useful when the surrounding surface of the road 100 has been exposed to sunlight for an extended period of time or frequently driven over by vehicles.

In another embodiment, the sensors 230 may include piezoelectric sensors, which may produce electrical power from pressure, strain and/or force applied thereto by, for example, vehicles passing over. The sensors 230 may include a mixture of a thermocouple sensor, piezoelectric sensor and/or other types of sensory devices.

The electric power produced by the sensors 230 may be stored in the power storage 210. In an embodiment, the energy storage 210 may include a battery. The disclosure also contemplates substitution of the battery for a capacitance device or the like to store the electric power. Moreover, the capacitance device or the like may be used in combination with a battery.

The switch 220 may be coupled between the energy storage 210 and the heating devices 240 in order to selectively power the heating devices 240 depending on the surface temperature of the road 100. For example, the switch 220 may power the heating devices 240 when the surface temperature drops, or is about to drop below a certain temperature, such as, e.g., the freezing point of water The switch 220 may stop powering the heating devices 240 when the surface temperature rises above a certain temperature, such as, e.g., a melting point of ice. This may help conserve the electric power stored in the power storage 210. The heating devices 240 may include a resistive heating element, which may convert the electric power from the energy storage 210 to heat.

According to the disclosure, when the surface temperature drops, or is about to drop below the freezing point of water, the collective heat generated by the bulk of the road heating devices 200 may increase the surface temperature of the road 100. This may reduce or prevent the rain or snow accumulated on the road 100 from turning to ice. Also, the ice already formed on the road 100 may be melted due to the increased surface temperature. Therefore, the hazardous winter driving conditions may be significantly improved, and accidents and casualties may be reduced or prevented.

FIG. 4 shows a flowchart 400 of a process for increasing a surface temperature of a road according to the principles of the disclosure. Upon starting the process at step 410, an environmental impact, physical impact and/or other types of impacts on a road surface may be converted to electric power at step 420. The environmental impact may include heat conducted from the road surface and/or the like. The physical impact may include a pressure, force, strain and/or the like, on the road surface by, for example, vehicles passing over. Other types of impacts that are convertible to electric power are also contemplated. At step 430, the electric power may be stored.

While the surface temperature is higher than the freezing point of water at step 440, no step may be taken to increase the surface temperature, and the environmental, physical and/or other impacts may continue to be converted to electric power at step 420. However when the surface temperature drops, or is about to drop below the freezing point of water at step 440, the stored electric power may be converted to heat in order to increase the surface temperature at step 450. While the surface temperature remains lower than the melting point of ice at step 460, the stored electric power may be continuously converted to heat at step 450. This conversion from electric power to heat may continue until the electric power is completely consumed. When the surface temperature reaches or surpasses a melting point of ice at step 460, the stored electric power may no longer be converted to heat at step 470, and the process may loop back to converting the environmental impact, physical impact and/or other impacts to electric power at step 420.

By converting electric power to heat when the temperature approaches or drops below the freezing point of water, the process of FIG. 4 may reduce or even prevent rain, condensation, moisture, snow, or the like, accumulated on the road surface from turning to ice. Furthermore, by increasing the surface temperature, the ice already formed on the road 100 may be melted. Therefore, the process of FIG. 4 may improve the hazardous winter driving conditions and reduce accidents and casualties due to hazardous winter road conditions.

While the disclosure has been described in terms of exemplary embodiments, those skilled in the art will recognize that the disclosure can be practiced with modifications in the spirit and scope of the appended claims. These examples given above are merely illustrative and are not meant to be an exhaustive list of all possible designs, embodiments, applications or modifications of the disclosure. 

1. A road heating device disposable on a road to increase a surface temperature thereof, comprising: a sensor configured to convert at least one of an environmental impact and a physical impact on the road heating device to electric power; an energy storage configured to store the electric power from the sensor; a heating unit configured to generate heat using the electric power stored in the energy storage; and a switch configured to selectively power the heating unit with the electric power stored in the energy storage when the surface temperature is equal to or lower than a first temperature.
 2. The road heating device of claim 1, being micro-sized or nano-sized.
 3. The road heating device of claim 1, wherein the environmental impact comprises heat conducted from the road to the road heating device.
 4. The road heating device of claim 3, wherein the sensor comprises a thermocouple sensor.
 5. The road heating device of claim 1, wherein the physical impact comprises at least one of a pressure, a force and a strain to the road heating device.
 6. The road heating device of claim 5, wherein the sensor comprises a piezoelectric sensor.
 7. The road heating device of claim 1, wherein the energy storage comprises at least one of a battery and capacitor.
 8. The road heating device of claim 1, wherein the heating unit comprises a resistive heating element.
 9. The road heating device of claim 1, wherein the first temperature comprises a freezing point of water.
 10. The road heating device of claim 1, wherein the switch stops power from being supplied to the heating unit when the surface temperature is equal to or higher than a melting point of ice.
 11. The road heating device of claim 1, wherein the road heating device is disposed on asphalt pavement, embedded in a surface coating on asphalt, or embedded in a pavement structure.
 12. A method for increasing a surface temperature of a road, comprising: converting at least one of an environmental impact and a physical impact to the road to electric power; storing the electric power; and converting the stored electric power to heat when the surface temperature of the road is equal to or lower than a first temperature.
 13. The method of claim 12, wherein the environmental impact comprises heat conducted from the road, and the physical impact comprises at least one of a pressure, a force and a strain to the road.
 14. The method of claim 12, wherein the first temperature comprises a freezing point of water.
 15. The method of claim 14, further comprising stop converting the stored electric power to heat when the surface temperature is equal to or greater than a melting point of ice.
 16. A device for increasing a surface temperature of a road, the device comprising a plurality of road heating devices disposed on the road, each road heating device comprising: a first converting unit configured to convert at least one of an environmental impact and a physical impact to electric power; an energy storage unit configured to store the electric power from the first converting unit; a second converting unit configured to convert the electric power stored in the energy storage unit to heat; and a switching unit configured to power the second converting unit when the surface temperature is equal to or lower than a first temperature.
 17. The device of claim 16, wherein each road heating device is micro-sized or nano-sized.
 18. The device of claim 16, wherein the environmental impact comprises heat conducted from the road to the road heating device, and the physical impact comprises at least one of a pressure, a force and a strain to the road heating device.
 19. The device of claim 16, wherein the first temperature comprises a freezing point of water.
 20. The device of claim 19, wherein the switching unit stops power from being supplied to the second converting unit when the surface temperature is equal to or higher than a melting point of ice. 